PowerBuilder

Azure Key Vault Sign with a Certificate's Private Key

See more Azure Key Vault Examples

Signs a hash using the private key of a certificate previously imported to an Azure Key Vault. PowerBuilder

integer li_rc
integer li_Success
oleobject loo_Json
oleobject loo_Sb
string ls_SignedString
string ls_Hash_base64url
oleobject loo_JsonBody
oleobject loo_Http
string ls_Url
oleobject loo_Resp
integer li_StatusCode
oleobject loo_JsonResp
oleobject loo_Cert
oleobject loo_Rsa
integer li_Valid

li_Success = 0

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// See Azure Key Vault Get Certificates for a more detailed explanation
// for how Chilkat is automatically getting the OAuth2 access token for your application.

// Provide information needed for Chilkat to automatically get an OAuth2 access token as needed.
loo_Json = create oleobject
li_rc = loo_Json.ConnectToNewObject("Chilkat.JsonObject")
if li_rc < 0 then
    destroy loo_Json
    MessageBox("Error","Connecting to COM object failed")
    return
end if
loo_Json.UpdateString("client_id","APP_ID")
loo_Json.UpdateString("client_secret","APP_PASSWORD")
loo_Json.UpdateString("resource","https://vault.azure.net")
loo_Json.UpdateString("token_endpoint","https://login.microsoftonline.com/TENANT_ID/oauth2/token")

// In this example, we'll sign the SHA256 hash of the string "This is a test"
loo_Sb = create oleobject
li_rc = loo_Sb.ConnectToNewObject("Chilkat.StringBuilder")

ls_SignedString = "This is a test"
loo_Sb.Append(ls_SignedString)
ls_Hash_base64url = loo_Sb.GetHash("sha256","base64url","utf-8")

// We're going to send a POST to the following URL:
// POST {vaultBaseUrl}/keys/{key-or-cert-name}/{key-or-cert-version}/sign?api-version=7.4

// For example:

// POST https://VAULT_NAME.vault.azure.net/keys/CERT_NAME/CERT_VERSION/sign?api-version=7.4
// 
// {
//   "alg": "RS512",
//   "value": "RUE3Nzg4NTQ4QjQ5RjFFN0U2NzAyQzhDNEMwMkJDOTA1MTYyOTUzNjI5NDhBNzZDQTlFOTM1NDA2M0ZGMjk2Mg"
// }

// The alg can be one of the following
// ES256  ECDSA using P-256 and SHA-256
// ES256K ECDSA using P-256K and SHA-256
// ES384  ECDSA using P-384 and SHA-384
// ES512  ECDSA using P-521 and SHA-512
// PS256  RSASSA-PSS using SHA-256 and MGF1 with SHA-256
// PS384  RSASSA-PSS using SHA-384 and MGF1 with SHA-384
// PS512  RSASSA-PSS using SHA-512 and MGF1 with SHA-512
// RS256  RSASSA-PKCS1-v1_5 using SHA-256
// RS384  RSASSA-PKCS1-v1_5 using SHA-384
// RS512  RSASSA-PKCS1-v1_5 using SHA-512

// The sample POST above uses SHA512.  We'll instead sign a SHA256 hash..

loo_JsonBody = create oleobject
li_rc = loo_JsonBody.ConnectToNewObject("Chilkat.JsonObject")

loo_JsonBody.UpdateString("alg","RS256")
loo_JsonBody.UpdateString("value",ls_Hash_base64url)

loo_Http = create oleobject
li_rc = loo_Http.ConnectToNewObject("Chilkat.Http")

// Instead of providing an actual access token, we give Chilkat the information that allows it to 
// automatically fetch the access token using the OAuth2 client credentials flow.
loo_Http.AuthToken = loo_Json.Emit()

loo_Http.SetUrlVar("certName","importCert01")
loo_Http.SetUrlVar("certVersion","7140c8755ed14839b5d86a9f7e7f0497")
// Note: Replace "VAULT_NAME" with the name of your Azure key vault.
ls_Url = "https://VAULT_NAME.vault.azure.net/keys/{$certName}/{$certVersion}/sign?api-version=7.4"
loo_Resp = create oleobject
li_rc = loo_Resp.ConnectToNewObject("Chilkat.HttpResponse")

li_Success = loo_Http.HttpJson("POST",ls_Url,loo_JsonBody,"application/json",loo_Resp)
if li_Success = 0 then
    Write-Debug loo_Http.LastErrorText
    destroy loo_Json
    destroy loo_Sb
    destroy loo_JsonBody
    destroy loo_Http
    destroy loo_Resp
    return
end if

li_StatusCode = loo_Resp.StatusCode

loo_JsonResp = create oleobject
li_rc = loo_JsonResp.ConnectToNewObject("Chilkat.JsonObject")

loo_Resp.GetBodyJson(loo_JsonResp)

loo_JsonResp.EmitCompact = 0
Write-Debug loo_JsonResp.Emit()

if li_StatusCode <> 200 then
    Write-Debug "Failed."
    destroy loo_Json
    destroy loo_Sb
    destroy loo_JsonBody
    destroy loo_Http
    destroy loo_Resp
    destroy loo_JsonResp
    return
end if

// A successful response body contains JSON like this:
// Note: Azure's documentation is not very clear, but base64url is the encoding, not "base64".
// {
//   "kid": "https://kvchilkat.vault.azure.net/keys/importCert01/7140c8755ed14839b5d86a9f7e7f0497",
//   "value": "JzWd2YF21gjtW ... Em37hKOQ"
// }

// Let's validate the signature using the cert's public key.
// This example will load the corresponding certificate from a local file and will verify the signature against the original data.
// 
loo_Cert = create oleobject
li_rc = loo_Cert.ConnectToNewObject("Chilkat.Cert")

li_Success = loo_Cert.LoadFromFile("qa_data/certs/chilkat_code_signing_2024.cer")
if li_Success = 0 then
    Write-Debug loo_Cert.LastErrorText
    destroy loo_Json
    destroy loo_Sb
    destroy loo_JsonBody
    destroy loo_Http
    destroy loo_Resp
    destroy loo_JsonResp
    destroy loo_Cert
    return
end if

loo_Rsa = create oleobject
li_rc = loo_Rsa.ConnectToNewObject("Chilkat.Rsa")

// Tell the RSA object to use the cert's public key.
li_Success = loo_Rsa.SetX509Cert(loo_Cert,0)
if li_Success = 0 then
    Write-Debug loo_Rsa.LastErrorText
    destroy loo_Json
    destroy loo_Sb
    destroy loo_JsonBody
    destroy loo_Http
    destroy loo_Resp
    destroy loo_JsonResp
    destroy loo_Cert
    destroy loo_Rsa
    return
end if

// Verify the signature using the cert's public key against the original string.
loo_Rsa.EncodingMode = "base64url"
li_Valid = loo_Rsa.VerifyStringENC(ls_SignedString,"sha-256",loo_JsonResp.StringOf("value"))
Write-Debug "signature valid = " + string(li_Valid)


destroy loo_Json
destroy loo_Sb
destroy loo_JsonBody
destroy loo_Http
destroy loo_Resp
destroy loo_JsonResp
destroy loo_Cert
destroy loo_Rsa